Question 1

Refer to the first image (spirographic record). Which labeled volume (A–H) represents the amount of air that can be forcibly exhaled after a normal tidal expiration, and what is the physiological significance of this volume?

Accepted Answer

C; it represents the expiratory reserve volume, which is important for removing additional air from the lungs during forced expiration.

Question 2

According to Boyle’s law, what happens to the pressure inside the lungs when the thoracic cavity volume increases during inspiration?

Accepted Answer

The pressure decreases, causing air to flow into the lungs. $$P_1V_1 = P_2V_2$$

Question 3

Which of the following best describes the function of the nasal conchae in the upper respiratory system?

Accepted Answer

They increase the mucosal surface area and enhance air turbulence, aiding in warming, humidifying, and filtering incoming air.

Question 4

A patient with emphysema has impaired pulmonary gas exchange, leading to CO$$_2$$ accumulation. According to the bicarbonate buffer system, what will happen to their blood pH?

Accepted Answer

Blood pH will decrease due to increased H$$^+$$ concentration: $$\mathrm{CO_2$ + H_2O \rightarrow H_2CO_3 \rightarrow H^+ + $$HCO_3$$^-}$$

Question 5

Refer to the second image (oxygen-hemoglobin dissociation curve). Why is the steep portion of the curve at lower PO$$_2$$ values physiologically important?

Accepted Answer

It allows hemoglobin to unload large amounts of O$$_2 to $$tissues where PO$$_2 is $$low, ensuring adequate oxygen delivery during increased metabolic demand.

Question 6

Which of the following is the main stimulus for increased bile secretion from the liver?

Accepted Answer

Return of bile salts from enterohepatic circulation.

Question 7

During swallowing, what is the role of the epiglottis as shown in the third image?

Accepted Answer

It bends to cover the laryngeal inlet, preventing food from entering the airway.

Question 8

Which of the following cell types in the liver lobule (see fourth image) is responsible for removing bacteria and debris from the blood?

Accepted Answer

Stellate macrophages (Kupffer cells)

Question 9

Which structural modification of the small intestine (see fifth image) is primarily responsible for increasing the absorptive surface area?

Accepted Answer

Villi and microvilli, which increase surface area for nutrient absorption.

Question 10

Which process is primarily responsible for moving feces toward the rectum in the large intestine (see sixth image)?

Accepted Answer

Mass movements (strong peristaltic contractions)

Question 11

Which of the following best describes the function of surfactant in the alveoli?

Accepted Answer

It reduces alveolar surface tension, preventing alveolar collapse.

Question 12

A patient has a tidal volume of 500 mL and an anatomical dead space of 150 mL. What is their alveolar ventilation per breath?

Accepted Answer

$$500\ \mathrm{mL} - 150\ \mathrm{mL} = 350\ \mathrm{mL}$$

Question 13

Which of the following is a function of the paranasal sinuses?

Accepted Answer

They lighten the skull.

Question 14

Which enzyme is responsible for the initial chemical digestion of starch in the mouth?

Accepted Answer

Salivary amylase

Question 15

Which layer of the alimentary canal is responsible for segmentation and peristalsis?

Accepted Answer

Muscularis externa

Question 16

Which of the following is true regarding the transport of oxygen in the blood?

Accepted Answer

Most oxygen is transported bound to the heme group of hemoglobin.

Question 17

Which of the following factors will decrease hemoglobin’s affinity for oxygen, promoting oxygen unloading at the tissues?

Accepted Answer

Increased temperature, increased PCO$$_2$$, increased BPG, and decreased pH.

Question 18

Which of the following is the main function of the large intestine?

Accepted Answer

Absorption of water and elimination of feces.

Question 19

Which of the following best describes the movement of gases during pulmonary gas exchange?

Accepted Answer

O$$_2$$ diffuses from alveoli to blood, and CO$$_2$$ diffuses from blood to alveoli, both moving from higher to lower partial pressure.

Study Guidance for Pulmonary Volumes, Hemoglobin Saturation, Swallowing, Liver Histology, Small Intestine Structure, and Large Intestine Anatomy

Study Guide - Practice Questions

Study Guide - Flashcards